The postwar US technical mission to Japan was of the opinion that a Yamato class battleship would sink if hit by four torpedoes on the same side of the ship. Obviously it would take longer to sink than Shinano, but I believe the issue is loss of stability due to inability to rapidly counter flood the opposite side of the ship.

Bgile wrote:The postwar US technical mission to Japan was of the opinion that a Yamato class battleship would sink if hit by four torpedoes on the same side of the ship. Obviously it would take longer to sink than Shinano, but I believe the issue is loss of stability due to inability to rapidly counter flood the opposite side of the ship.

Very interesting! I dind't knew that...But I think their findings had much to do with the more powerfull torpedoes explosive charges used by the US Navy... (warhead 200kg Torpex)

he postwar US technical mission to Japan was of the opinion that a Yamato class battleship would sink if hit by four torpedoes on the same side of the ship.

I believe they were talking about four simultaneous torpedo hits evenly spaced within the citadel. The USN calculated that five or six similar torpedo hits would overwhelm the counterflooding and liquid transfer capacity of an Iowa class battleship and lead to capsizing and sinking of the ship.

Their shoulders held the sky suspended;They stood and Earth's foundations stay;What God abandoned these defended;And saved the sum of things for pay.

he postwar US technical mission to Japan was of the opinion that a Yamato class battleship would sink if hit by four torpedoes on the same side of the ship.

I believe they were talking about four simultaneous torpedo hits evenly spaced within the citadel. The USN calculated that five or six similar torpedo hits would overwhelm the counterflooding and liquid transfer capacity of an Iowa class battleship and lead to capsizing and sinking of the ship.

Coming back to the Vanguard, does anyone know what the gun life between relinings was for supercharged 15 in guns? The figure for normal charges was 335. I know this is a rather academic question because only two 15 in guns were actually ever used with supercharges (coastal guns at Dover).It appears that after the Action at Calabria, where all the RN battleships except the Warspite were outranged by the Cavours and Italian heavy cruisers, the RN decided it needed a quickfix for the old battleships that still had only 20 deg elevation for the main guns. By 1942 they were fitted with supercharges, 15% up on the standard ones giving an MV of 2638 ft/s compared to 2458 ft/s (increase in KE also 15%). However, these were never used, presumably because by then these ships were used only for shore bombardment where gun life rather than range would have been more important. The Vanguard had strengthened mountings to allow use of supercharges with up to 30 deg elevation, but again these were never used, perhaps because by then there were no potential enemy battleships.Full range data for supercharges were given for an average MV of 2575 ft/s, the same as the derated French 15 in gun. So, presumably (potential) armor penetration would be only slightly less than that given for the French 15 in gun in Dulin & Garzke (as the British shell weighed 11 lb less). The official data for 2575 ft/s show a weapon that was superior in flight time and angle of fall to the Mark I 16 in gun. Deck penetration would have probably been poor though. The only question is: at what cost in gun life was this improvement bought? It must have been substantial, although still likely to have been better than the short life Italian 15 in guns.

The navweapons site (http://www.navweaps.com/Weapons/WNBR_15-42_mk1.htm) mentions that a 3/4 charge resulted in reducing the wear to 1/4 of what it normally would be. A very rough linear extrapolation would indicate that the ~13% bigger supercharge would increase wear actor to 1 and 3/8 that of a standard charge. If you assume the increase should be porportional then it would be equivalant to 2 standard charges. I suspect it would be higher than the first.

Thank you for this suggestion. My calculation using this is as follows. Normal life (for 432 lb charge) = 335 rounds. Life with 4/3 charge (576 lb) = 335/4 = 83 rounds (purely theoretical!). Interpolating for a supercharge (490 lb) gives 230 rounds. Increase in wear = 45.6% (more than the 37.5% increase I think you mention). With this, the loss of MV/round = 0.55 ft/s (supercharge) compared with 0.35 ft/s (normal round). Such a life would seem acceptable, although a mixture of charges would probably be better, reserving the supercharges for actions with battleships. The higher MV had other advantages: lower elevation for a given range (and possible tendency to higher rof) and shorter flight times (greater probability of a chance hit at long range). Danger space and dispersion would have both increased. An MV of 2575 ft/s (average) would have given the Vanguard a good punch for the 3420 tons weight of the four turrets (855 tons each) and even the about 4920 tons combined weight of turrets and barbettes.By way of comparison, Campbell in an early Warship article say that the 16 in Mark I had initial initial figures of: MV = 2670 ft/s;life = 180 efc (at most); wear = 1.5 ft/s per round. This life was too short for the RN although he says some others might have found it acceptable, and the MV was reduced to 2586 ft/s.It would be interesting to know how the RN arrived at the range tables and flight times having only two operational guns. Were the figures mainly theoretical?Of note on that NavWeapons piece on the 15 in is a quote from ADM 186/251 regarding tests at reduced MVs to simulate hits at long range: It talks about "unsteadiness of shells", tests having to be repeated, and shells going through "jump cards" before striking the plate. "Unsteadiness' sounds like yaw.

She looks to me like a beautifully balanced design, which incorporated many improvements over KGV that made her greater than the sum of the individual parts and far better. She was a better sea boat as well as faster and better able to absorb damage(damaged stability was rather good), never mind quite good to look at as well. The only chinck in the armor that I could think of was that she seems vulnerable to anything penetrating the armored belt.(refer Dunkerque which was disabled by only a hand full of shells that penetrated the armored belt. Would have preferred to see the armored with slopes to give added protection.

Billy wrote:She looks to me like a beautifully balanced design, which incorporated many improvements over KGV that made her greater than the sum of the individual parts and far better. .

Indeed the RN's very own (almost) Bismarck.

The only chinck in the armor that I could think of was that she seems vulnerable to anything penetrating the armored belt.(refer Dunkerque which was disabled by only a hand full of shells that penetrated the armored belt. Would have preferred to see the armored with slopes to give added protection.

By making the belt less steeply sloped it reduced the vulnerablity to diving shells. Strickly speaking it was sloped where it followed the contour of the hull.

I used the Gkdos100 curves vs KCnA for 38.1cm 875kg projectile and inputed the striking velocity and striking angle for the Vanguard's 1938lb 6chr shell using standard service charges. (The results are probably slightly over stated at these ranges because the British shell main body head shape was 1.4 caliber radius) at 20,000 yards the penetration is about 15.8". At 22,000 yards the penetration is about 14.2-inches, so Vanguard's belt was well suited to provide a IZ extending from 20km to 30km vs its own gun.

Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.

I think the G3 reflected the times of its design. With the advent of more deadly projectiles such as the British Green Boys, the previous convenient rules of thumb that a belt thickness equal to the caliber it was designed to resist was sufficient, or that the armored deck need be nothing more than a splinter shield, no longer held. Hence a real armored deck had to be incorporated. Previous designs, even those considered AON, did not really have armored decks of significance. For example, WV’s main armored deck was only 1.5” of STS laid directly over 1.5” of mild steel! To pay for the weight of incorporating a real armored deck we find other design features such as an internal armored raft, sloped belts, and a truncated citadel.

But we are also seeing a redefinition of what battle ranges the ship should be protected. Part of this is advancements of firecontrol which made longer battle ranges more practical, but some of it the simple fact that it was now becoming impossible to provide protection inside of about 20,000 yards among battleships.

Battleship design then entered a period of stagnation with the moratorium not only of new construction, but also cut backs or out right suspension of R&D. When the French started Dunkerque they essential picked up right where the RN stopped with the G3 years previous.

Ironically the British themselves began walking back several of the design tenants of the G3 as they began to workup what eventually became KGV. With the KGV the British returned to an external belt, a longer protected length, and went to greater volume inside the citadel. The KGV design tells us what were now seen as weakness with the G3. In other words the power of newer weapons and other considerations had made the G3 design concept somewhat dated.

The Germans also recognized the new need for significant deck armor. According to Bericht 166 Lilienthalgesellschaft, deck armor needs was the driving factor behind the protection system adopted by the Germans. The German concept allowed weights committed to horizontal protection to also enhance vertical protection.

Entering a night sea battle is an awesome business.The enveloping darkness, hiding the enemy's.. seems a living thing, malignant and oppressive.Swishing water at the bow and stern mark an inexorable advance toward an unknown destiny.

Dave Saxton wrote:Ironically the British themselves began walking back several of the design tenants of the G3 as they began to workup what eventually became KGV. With the KGV the British returned to an external belt, a longer protected length, and went to greater volume inside the citadel. The KGV design tells us what were now seen as weakness with the G3. In other words the power of newer weapons and other considerations had made the G3 design concept somewhat dated. .

I think the example of POW being so easily sunk by the Japanese demonstrates that the design wasn't that much of a success.